Lighting unit



Nov. 13, 1934. D H. TUCK -f AL 1,980,773

LIGHTING UNIT Filed Dec. '51, 1951 ATTORNEY n Patented Nov. 13, 1934UNITED STATES LIGHTING UNIT Davis H. Tuck, Norwalk, Conn., and WilsonRosebraugh, Newark,

Ohio, assignors to Holophane Company, Inc., New York, N. Y., acorporation of Delaware Application December 31, 1931, Serial No.'84,084

4 Claims.

The present invention relates to lighting unit and is more particularlydirected toward lighting units designed for outdoor use and forilluminating objects above the level of the lighting unit at 5comparatively high intensity and for providing a small amount ofdownwardly directed light for general illumination.

Outdoor lighting such as street and yard lighting is generally designedto effect a desired light l0 distribution on levels below the level ofthe lighting units employed. They are intended to light the entire areaas evenly as possible consistent with the mounting height of the units,the spacing employed, and characteristics of the units used.

The lighting source and light controlling means, such as refractor orreflector may, in this type of construction, be individually supportedso that the proper adjustments of light source and refractor may be madeto accurately focus the lamp and secure the maximum eiiciency of therefractor.

The present invention contemplates a lighting unit more especiallydesigned for outdoor use such as in lighting transmission linesubstations where it is desired to illuminate wires, lighting arresters,

disconnecting switches, and the like which are above the lights. Formore eicient use of the light and its accurate direction, a refractingunit is preferably employed about the light source.

The present invention provides a lower diffuser `adapted to receivedownwardly directed light which escapes below the refractor. Thisdiffuser acts to diffuse and transmit this light downwardly for generalillumination below the lighting unit.

The invention also contemplates an outdoor lighting luminair having therefractor and protective envelope so supported as to permit interiorventilation of the unit, especially between the refractor and theprotective envelope.

The accompanying drawing shows, for purposes zioof illustrating thepresent invention, two of the many embodiments in which the inventionmay take form, it being understood that the drawing is illustrative ofthe invention rather than limiting the same. In the drawing:

Fig. 1 is a vertical sectional View through a lighting unit embodyingthe present invention with parts in section and showing in dot-and-dashlines the unit partially open;

Fig. 2 is a sectional view taken on the line 2-2 5010i Fig. 1 with partsbroken away; and

Fig. 3 is a fragmentary view illustrating a modincation.

The present form of lighting unit is provided with a suitable support,such as a tubular memlber 11 adapted to be tightly secured to the top of(Cl. 24U-25) a post or to al bracket or other device. This member isinternally flanged as indicated at 12 to sup,- port a lamp socket 13.This lamp socket is adapted to carry a lamp bulb 14 with itsl axisvertical. The outside of the tubular member 11 is threaded as indicatedat 15 to receive a castingl.

As shown in Fig. 1', this casting has an inner ring-like portion 1'7threaded to t the member 11, an outer ring-like portion 18 ofcomparatively large diameter, and anumber of curved ribs 19interconnectingA the two ring-like portions. At the right hand side ofthe drawing, the ring-like member 13 carries an upwardly extending lug20 provided with a hinge pin 21. The opposite side of the ring-likemember 18 carries a locking screw 22.

An upper ring 25 has lugs 26'mounted on hinge pin 21 and has anextension 27 to receive a threaded clamp member 22. The ring 25 has adepending rib 28 adapted'to rest on the outer surface Aof a bead 29`provided in the ring-like member 18. The ring 25 extends inwardly asindicated at 30 to vprovide an annular trough 31 adapted to receivel thelower edge of the outer protecting'envelope 32. 'This envelope issecured in place by clamping screws indicated at 33.

The ring 25 has a number of inwardly extending arms indicated at 34 tosupport an inner ring 35, generally cast integral therewith. This innerring is of a size to support an inverted bowl type refractor 36 of theusual type. This refractor is clamped in place by locking members 37secured on posts 38.

The frame 16 is designed to receive a diffusing bowl 40. This may bemade of crystal glass provided with diffusing corrugations, or any otherform of diffusing glass and colored, if desired. This bowl is secured tothe casting 16 by clamping devices indicated at 41 and packing rings 42and 43 are employed to make a weather tight joint between the parts. Therefractor 36 is adapted to concentrate the light into vupwarddirections, such for example as indicated by the photometric curves A-Ain Fig. l. Where a twoway asymmetric refractor is used, horizontaldistribution may be as indicated by the curves B-B of Fig. 2. Thefocusing of the lamp and the orientation of the asymmetric beams areaccomplished by revolving the entire unit about the threaded support,the unit being clamped in place by a lock nut indicated at 44.

It will be noted that the refractor 36 is open at the bottom. Thisallows a certain part of the light to escape downwardly. It falls on tothe diiiuser as indicated by the light ray 45 and .ics

this diffuser scatters the light as indicated, thereby providing lightfor illuminating the ground and surrounding objects. If the downwardillumination is not desired, an opaque shield may be substituted for thediffuser or a casting 16 may be designed so as to form the closed bottomof the unit optically'as well as physically. This is indicated in Fig.3.

It will be noted that the refractor is supported by the arms 34 so as tobe some distance inside the protective envelope and that the arrangementaffords large passages 46 for air circulation inside the lamp unit. Theair can pass through these openings and, owingv to the largel exposedsurface of the protective envelope, the unit can be operated with'lessheating of the refractor.

It is obvious that the invention may be embodied in many forms andconstructions, and we wish it to be understood that the particular formsshown are but two of the many forms.

Various modications and" changes being possible, we do not otherwiselimit ourselves in any` i ing ring secured tothe frame member andcarryving the refractor, an'outer protective envelope carried by thering, and meansto clamp the ring and frame member together.

2. A luminair comprising an upright lamp bulb,'a refractor open"at thebottom and disposed about the lamp bulb for concentrating light intoupward. directions, a diffusing bowl of larger outside diameter than therefractor placed below the refractor for receiving andtransmitting indownward directions the direct light emitted below the refractor, askeleton frame member to receive the bowl and having an upper ring-likeportion, a ring hingedly secured to the ring-like portion of the framemember and having an inner` portion and an outer portion clamped againstthe frame member, the inner portion supporting the refractor, and anouter protective envelope secured to the outer portion of the ring.

3. A luminair comprising an upright lamp bulb, a refractor open at thebottom and disposed about the lamp bulb for concentrating light intoupward directions, a diffusing bowl of larger outside diameter than therefractor placed below the refractor for receiving and transmitting indownwarddirectionsjthe direct light emitted below the refractor, askeleton frame member to receive the bowl and having an upper ring-likeportion, a` ring hingedly secured to the ring-like portionof the framemember and having an inner portion and an outer portion clamped againstthe frame member, the inner portion supporting the refractor, and anouter protective envelope, secured to the outer portion of the ring,there being large openings in the ring between the refractor andenvelopeto facilitate interior ventilation.

4. An outdoor lighting fixture comprising an upwardly opening lampsocket, a lamp bulb therein, a lamp socket support, a dish-shapeddiffusing glass bowl extending upwardly and outwardly from the lampsocket, a bowl support secured to the socket support and having aringlike portion about the upper edge of the glass,`

bowl, a ring hingedly secured to the first ring to rest on the upperface thereof, a refractor supported from said ring adjacent the lampbulb, and an outer protective envelope carried by the ring about therefractor, there being large openings in the ring between therefractor'and envelope to facilitate the flow of air currents inside thefixture.

- DAVIS H. TUCK.

WILSON ROSEBRAUGH.

